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Discussion Starter #1
Hey Guys, I'm , having a transmission issue.
Started around 2 months ago
Trans temp gauge quit working
Gear indicator light quit working
Tow / Haul lights up on dash, but isn't working
Overdrive lock out lights up on dash but doesn't work
Doesn't want to downshift, when going up hills, or after slowing down. sometimes it does, sometimes it doesn't

What should I bee looking for
 

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First thing for me is always to check electrical (plugs at the TCM and Trans) Kinda sounds like too many 'trans' things all at once to not be electrical, or a failing TCM.
 

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First check the condition of all the wiring around your transmission.
 
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As the other guys have already pointed out, check all of the wiring going into the tranny.

If the wiring shows no signs of damage, you are most likely looking at a bad TCM, especially considering the miles on your truck if the TCM hasn't been replaced already.
 

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th plumber,

That temp gauge is an easy stepper motor replacement fix, if you can do soldering of electronics.

Several YouTube video how to's and the stepper motors (one for each dial on the dash) are cheap to buy on eBay, 8 for $12 or so. Took me about an hour to pull the instrument panel, take the thing apart, solder in 3 stepper motors for the ones that quit, and reassemble everything.
 

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Discussion Starter #6
Thanks, for the replies guys!
The guys at Leadfoot Diesel told me that their scan tool couldn't communicate with the transmission. Since I'm trying to get through a busy stretch, and it's not really affecting anything, I told them I would bring it in later in January. Said they think its a plug inside the trans and they would have to drop the pan to get to it.
I have seen a couple of posts where there was a dead wire from the tcm to the trans, and the dealer mechanic spliced in a new wire.
I think I will leave it to the pros and I'll stick to Plumbing!
 
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